In a projector of related art, since a projection optical system that enlarges and projects an image formed on a planar display device is used, a plane where focus is achieved is a substantially flat plane, and allowed adjustment is only shifting the plane forward or rearward. That is, change in focus position and simultaneous or concurrent projection in projection receiving areas at different depth positions are not allowed, and there has been no projector capable, for example, of performing projection on a curved screen with focus maintained over the surface or coping with a change in the shape of the curved screen.
Meanwhile, there is a technology that is not related to a projector but allows an imaging apparatus to acquire information on the direction of light incident on a two-dimensional sensor and simultaneously capture images of subjects at different distances in the depth direction (see PTL 1).